Sensor and sensor-equipped display device

Abstract

According to one embodiment, a sensor includes a first control line, a first signal line, a first detection switch, a common electrode, a first detection electrode, a first circuit and a second circuit. The common electrode is located above the first control line, the first signal line and the first detection switch, opposed to the first control line, the first signal line and the first detection switch. The first detection electrode is located above the common electrode. The first circuit and the second circuit are located under the common electrode, and are opposed to the common electrode.

What is claimed is: 
     
       1. A sensor comprising:
 a first control line; 
 a first signal line; 
 a first auxiliary line; 
 a first detection electrode; 
 a first detection switch connected to the first detection electrode, the first control line and the first signal line; 
 a second detection switch connected to the first detection electrode, the first control line and the first auxiliary line; 
 a first circuit connected to the first control line, and supplying a drive signal to the first control line to change a state of the first detection switch and the second detection switch to either of a first connection state and a second connection state; and 
 a second circuit connected to the first signal line and the first auxiliary line, 
 wherein 
 the first detection electrode is electrically connected to the first signal line and electrically disconnected from the first auxiliary line in the first connection state, and 
 the first detection electrode is electrically connected to the first auxiliary line and electrically disconnected from the first signal line in the second connection state. 
 
     
     
       2. The sensor of  claim 1 , wherein
 the second circuit writes a write signal to the first detection electrode via the first signal line and the first detection switch, reads a read signal indicating variation of the write signal from the first detection electrode, and supplies a potential adjustment signal to the first auxiliary line, in the first connection state, and 
 the potential adjustment signal is synchronized with the write signal and is equivalent in phase and amplitude to the write signal, in sensing drive of performing sensing. 
 
     
     
       3. The sensor of  claim 2 , further comprising:
 a first detection unit supplying a power source voltage to the first circuit; and 
 a superposition signal superposed on each of the drive signal and the power source voltage in the sensing drive, 
 wherein 
 the superposition signal is synchronized with the write signal and is equivalent in phase and amplitude to the write signal. 
 
     
     
       4. The sensor of  claim 2 , further comprising:
 a first detection unit supplying a control signal to the second circuit; and 
 a superposition signal superposed on the control signal in the sensing drive, 
 wherein 
 the superposition signal is synchronized with the write signal and is equivalent in phase and amplitude to the write signal. 
 
     
     
       5. The sensor of  claim 2 , further comprising:
 a shielding electrode located to overlap the first signal line, and connected to the first auxiliary line, 
 wherein 
 the first auxiliary line is electrically connected to the second circuit, and 
 the second circuit further supplies the potential adjustment signal to the shielding electrode via the first auxiliary line. 
 
     
     
       6. The sensor of  claim 2 , further comprising:
 a second signal line connected to the second circuit; 
 a second detection electrode; 
 a third detection switch connected to the second detection electrode, the first control line and the second signal line; and 
 a fourth detection switch connected to the second detection electrode, the first control line and the first auxiliary line, 
 wherein 
 the second circuit includes a first control switch for changing either of a first change state of supplying the write signal to the first signal line and a second change state of supplying the potential adjustment signal to the first signal line, and a second control switch for changing either of a first change state of supplying the write signal to the second signal line and a second change state of supplying the potential adjustment signal to the second signal line, and 
 the second circuit, in a sensing period of the sensing drive: 
 changes the first control switch to the first change state and the second control switch to the first change state, changes the first detection switch and the second detection switch to the first connection state by the drive signal, and changes the third detection switch and the fourth detection switch to the first connection state by the drive signal; 
 writes the write signal to the first detection electrode and reads the read signal indicating variation of the write signal from the first detection electrode, via the first control switch, the first signal line and the first detection switch; and 
 writes the write signal to the second detection electrode and reads the read signal indicating variation of the write signal from the second detection electrode, via the second control switch, the second signal line and the third detection switch. 
 
     
     
       7. The sensor of  claim 2 , further comprising:
 a second control line connected to the first circuit; 
 a third detection electrode; 
 a fifth detection switch connected to the third detection electrode, the second control line and the first signal line; and 
 a sixth detection switch connected to the third detection electrode, the second control line and the first auxiliary line, 
 wherein 
 the first auxiliary line is electrically connected to the second circuit, 
 the first circuit supplies the drive signal to the second control line, 
 the first detection switch and the second detection switch electrically connect the first signal line and the first detection electrode to each other in the first connection state, and electrically connect the first auxiliary line and the first detection electrode to each other in the second connection state, 
 the fifth detection switch and the sixth detection switch are changed to either of a first connection state of electrically connecting the first signal line and the third detection electrode to each other and a second connection state of electrically connecting the first auxiliary line and the third detection electrode to each other, by the drive signal, and 
 the second circuit, in a sensing period of the sensing drive: 
 changes the state of the first detection switch and the second detection switch to the first connection state and a state of the fifth detection switch and the sixth detection switch to the second connection state by the drive signal; 
 writes the write signal to the first detection electrode and reads the read signal indicating variation of the write signal from the first detection electrode, via the first signal line and the first detection switch; and 
 supplies the potential adjustment signal to the third detection electrode via the first auxiliary line and the sixth detection switch. 
 
     
     
       8. A sensor-equipped display device comprising a display panel,
 the display panel comprising: 
 a first control line; 
 signal lines including a first signal line; 
 auxiliary lines; 
 a first detection electrode; 
 a first detection switch connected to the first detection electrode, the first control line and the signal line, 
 a second detection switch connected to the first detection electrode, the first control line and the corresponding auxiliary line; 
 a first circuit disposed outside a display area, connected to the first control line, supplying a drive signal to the first control line, and changing a state of the first detection switch and the second detection switch to either of a first connection state and a second connection state; and 
 a second circuit disposed outside the display area, and connected to the signal lines and the auxiliary lines, 
 wherein 
 the first detection electrode is electrically connected to the first signal line and electrically disconnected from the corresponding auxiliary line in the first connection state, and 
 the first detection electrode is electrically connected to the corresponding auxiliary line and electrically disconnected from the first signal line in the second connection state. 
 
     
     
       9. The sensor-equipped display device of  claim 8 , further comprising:
 a pixel electrode and a common electrode opposed to the pixel electrode to generate an electric field therebetween in a display period, 
 wherein 
 the first detection electrode is arranged in the same layer as the pixel electrode. 
 
     
     
       10. The sensor-equipped display device of  claim 8 , wherein
 in a sensing period, the second circuit: 
 writes a write signal to the first detection electrode via the first signal line and the first detection switch, and reads a read signal indicating variation of the write signal from the detection electrode; and 
 supplies a potential adjustment signal which is synchronized with the write signal and is equivalent in phase and amplitude to the write signal. 
 
     
     
       11. The sensor-equipped display device of  claim 8 , further comprising:
 a pixel electrode and a common electrode opposed to the pixel electrode to generate an electric field therebetween in a display period; 
 a first detection unit connected to the display panel to control the drive of the first circuit and the second circuit; 
 a position detection sensor located in the display area of the display panel; and 
 a second detection unit connected to the position detection sensor, 
 wherein 
 in a detection period, in position detection drive of detecting position information of a detected object, the second detection unit drives the position detection sensor to detect the position information of the detected object, and 
 in the detection period, in sensing drive of detecting an uneven pattern of the detected object, the first detection unit sets a first detection electrode in an area where the detected object is located as a target of sensing, based on the position information, writes a write signal to the first detection electrode of the target of sensing via the second circuit, the first signal line and the first detection switch, reads a read signal indicating variation of the write signal from the first detection electrode, and supplies a potential adjustment signal which is synchronized with the write signal and equivalent in phase and amplitude to the write signal to the common electrode. 
 
     
     
       12. The sensor-equipped display device of  claim 9 , wherein
 the first detection electrode is located above the common electrode, and 
 the pixel electrodes and the detection electrode are disposed in a same layer.